Honing machine



March 22, 1938 I A. M. JOHNSON HONING MACHINE Filed Sept. 20, 1934 4 Sheets-Sheet l OMN s m w H H T n W m a O \OQN 99% V m A W www k N @M w WWW MQW k N mum ml. 22,1938, m oi-m sm 2,111,7 4

Filed Sept. '20, 1954 4 sheets-sheet s IN VENTQQ -March 22, 1938. A. M. JOHNSON -2,111,784

HONING MACHINE I 7 Filed Sept. 20, 1934 4 Sheets-Sheet 4 INVBNTOp P 'atented Mar; 22, 1938 f walls when inserting the tools or removing the UNITED STATES PATENT HONING MACHINE Albert M. Johnson, Rockford, Ill., assignor to Barnes Drill Company-,-Rockford, IlL, a corporation of Illinois Application September 20,1934, Serial No. 744,763

45 Claims.

a smooth, highly finished surface upon the, in-- terior of a hollow cylindrical body, and has especial reference to an improved machine of this character particularly adapted for operating upon surfaces disposed at an inclination to the horizontal. 1

Honing machines having fiexible reciprocably and rotatably mounted spindles carrying honing tools have been extensively employed to finish internal combustion engine cylinders arranged in vertical banks of 4 to 8, more or less. These machines have generally been provided with flexible spindles forcarrying the honing tools due to the inherent advantages of this construction. With these machines, however, it has been necessary to maintain an accurate vertical axial relationship between the hones and the cylinder bores in order to obviate any damaging 'eifects of the hone grinding stones upon the cylinder same from the bores. Thus, in'the case of V- type internal combustion engines in which the cylinders are disposed convergen'tly from opposite sides of the engine block towards a common center, it has been heretofore necessary first to hone vertically one bank of cylinders and thereafter turn the block around and bone the other in which the convergent cylinders can all be' which the diagonal cylinders of a V-type automotive engine block, or other cylindrical surfaces disposed diagonally to the horizontal, can be honed on a diagonal axis.

Another object of the invention resides in the provision of a machine of the foregoing char-' acter in which both the banks of convergent cylinders of a V-type internal combustion engine block may be simultaneously or independently honed with the base of the engine block supported in a horizontal plane.

Another object is to provide in. combination with a honing machine, means for supporting a work piece in position to receive the honing tool, and including improved means for accurately defining the position of the work piece relative to the honing tool as well as means-for retaining the work piece in such position until completion of the honing operation, together with control mechanism to synchronize operation of the positioning and retaining means.

Another object resides in the provision of a conveniently arranged work support adapted to receive a plurality of work pieces to be successively guided into position to be operated upon by the tool means of the machine, and including a hydraulically operated device adapted to be clamped against the work and serving to guide the tool means into the work piece.

Another object is to provide an improved guiding device for the tools, in which is incorporated means for delivering coolant positively and without splash to the tools when in working engagement.

novel arrangement of electrically controlled hydraulic means for operating the honing machine.

Another object of the invention is to provide a honing machine of the foregoing character havingpower driven means for rotating the honing tools, wherein a hydraulically operated clutch is provided for connecting or disconnecting the power from said means in synchronized relationship with the operation of the reciprocatory parts of the machine.

Other objects include the provision of .a single manual control member for operating the positioning, retaining and tool guiding means together with an electric master switch closable by said control member only after the completion of a predetermined sequence of operations; and an interlock for preventing operation of said control' member during a certain period of operation of the means controlled thereby.

Other objects and advantages will become apparent in the following description and from the accompanying drawings, in which:

Fig. 1 is a fragmentary perspective view of a machine embodying the features of the invention.

Fig. 2 is a sectional elevation showing details of the work support and associated mechanism.

Fig. 3 is a sectional elevation taken substantially on line 8-4 of Fig. 2. Fig. 4 is .a fragmentary sectional 'elevation showing details of the improved tool guiding and coolant delivery means.

Fig. 5 is an enlarged sectional plan view of a honing tool of a preferred type.

'Flg. 6 is a fragmentary sectional elevation through the honing tool taken substantially on line 15-60! Fig. 5. I

F g; 7 is an enlarged elevationof the control handle for controlling operation of the work positioning and tool guiding means and showing the relationship of the switch for electrical control of the honing machine.

Fig. 8 is a sectional elevation through the interlock taken substantially on line 8'3 of Fig. 7.

Fig. 9 is an enlarged: elevation taken online 9-3 of Fig. 2 and showing the arrangement for controlling the hydraulic operators for the work positioning and clamping and tool guiding mechanisms.

Fig. 10 is a schematic representation of the hydraulic, electrical and mechanical operating and control means and their relationship in the oper ation of the honing machine.

While the invention is susceptible of various modifications and alternative constructions, I have shown in the drawings and will herein describe in detail the preierred embodiment, but it is to be understood that I do not thereby intend to limit the invention to the specific form disclosed, but intend to cover all modifications and alternative constructions falling within the spirit and scope of the invention as expressed in the appended claims. I

Generally stated, the machine as illustrated herein comprises a substantially V-shaped supporting structure carrying reciprocatory heads from which depend convergent spindles carrying honing tools, and having a work standard between the said heads ior supporting a work piece in the form of a V-type cylinder block of an internalcombustion engine having diagonally disposed cylinder bores to be operated upon by the honing tools.. Suitable hydraulic means are provided for reciprocating the heads, and rotation 01' the spindles and tools is effected by suitable means hydraulically controlled to operate in synchronism with operation of the heads. Hydraulically operated means are provided in association with the work support for horizontally moving a cylinder block into operative position relative to means adapted to be clamped against the block for guiding the honing tools to the diagonal cylinder bores therein. Suflicient clearance is allowed between the latter means and the block.

during the positioning operation to permit free movement of the block. Suitable coolant is supplied to the tools while engaged with the cylinder walls, but due to the clearance. necessary during movement oi. the block together with the inclined disposition of the cylinder bores it is necessary to provide for positively conducting the.

coolant to the bores to avoid spilling-over or splash. Provision is therefore made to supply the coolant to the cylinder bores through the'honing tool guide means which is preferably arranged for substantially liquid-tight contact with the block. Operation of the entire machine is simplified and coordinated by means of manual and automatic mechanical as well as electrically actuated controls governed through conveniently located electric switches.

While the machine is shown and herein particularly described as provided with a pair 01' reciprocatory heads each having a bank of four hone spindles and adapted to operate upon internal combustion engine motor blocks, it will be apparent that any number of spindles may be provided and that the machine may be utilized for operating upon types of.work other than engine motor blocks.

More specifically described,the machine comprises a base i5 having a pair of upwardly and outwardly extending columns l6 and an intamediate work support I8, providing a substantially V-shaped structure. Each of the columns I6 preferably carries a similar arrangement of parts, so that a description of one will sufllce for the other.

As a matter of practical expediency and for purposes of illustration, the honing machine is shown as embodyinghone operating mechanism of substantially the same character as disclosed in Patent No. 1,783,019, issued November 25, 1930, to Albert M. Johnson.

At the upper end of the column I6 is mounted a main housing It having one or more auxiliary housings '20 extending therefrom toward theinside of the machine and with the lower end located above and facing toward the work support ID. Guide sleeves 22 extend through the auxiliary housings 20 and provide means for reciprocably guiding a head structure 23. The head structure supports a plurality of tool carrying spindles 25. herein shown as four in number. These spindles 25 are directed diagonally to the horizontal so as to extend axially of the bores of cylinders 21 The work support [8 is preferably constructed to receive a plurality of blocks 28 and to this end may be provided at one side with a receiving extension or knee 30 to increase substantially the working length 0! the support so that the blocks may be positioned for honing in rapid succession and without substantial interruption. A similar extension or knee (not shown) may be provided on the opposite side of the support i3 for receiving the blocks after they have been honed. A pair of parallel tracks 3| is carried by a longitudinal bridge member 32 supported by trusses 34 extending to each side and attached to the walls of the knee 30 or the body of base i8. The blocks 28 are slidably received on the tracks 3| and guide bars 38 and 31 prevent lateral displacement oi the blocks as the same are moved along the tracks 3|. The guides 36 and 31 are supported adjacent their outer ends by suitable means such as standards 38 secured as by bolts 39 to. the walls of the knee 33.

In order to move one of the blocks 28 along the tracks 3| and into position to be honed. mechanism, controlled to be operated in synchronism with other parts of the machine, is preferably provided for automatically actuating said 'one block into honing relation with the spindles 25, and simultaneously ejecting the preceding block which has already been honed. The mecha nism for this purpose may comprise an hydraulically operated indexing mechanism including a pawl 4| 'pivotally mounted by means of a pin 42 between the parallel sides 44 of a reciprocating carriage 45 (Figs. 2 and 3). The carriage 45 is supported for longitudinal movement on the bridge 32 by means of a roller 46 adjacent one or both of its ends, which roller is rotatably mounted in the carriage by means of a shaft 48 and rides on a track 49. Reciprocating movement is imparted to the carriage 45 by an hydraulically operated piston 50 (Fig. 10) reciprocable in a cylinder 5i and connected to astem 52 which has removably attached at its outer end a connecting member 54,- extending upwardly therefrom and connected to the carriage 45 by means of a pin 55. The member 54 is carried by a block 51 connected'to the end of the stem 52 by means of ret g disks 58 and 59 each of which has a collar 88 through which a set screw 8i passes to form a removable connection with the stem;

The pin 42 passes through 'the pawl4i in' oif center position so that what will be termed the rearward end of the lever will be pulled downwardly by the force of gravity to raise the for-' ward endjwhich has an abutment face 88 adapted to engage with the end of a block 28 to urge the same to the right, as viewed in Fig. 3, whenthe indexing mechanism is operated to move the carrlage48. The pawl H is freely rotatable so that when the carriage is moved to theleft, it will slide under the base of the following block 28 until it has reached the opposite end thereof, whereupon the abutment face 88 will be brought into position by gravity to bear against the said opposite end. A limit pin 85 extends through the from the track. after one of the blocks 28 has been positioned by the indexing mechanism, other mechanism will be broughtinto play to further prepare the machine for operating thereon.

The machine of the present invention, as has already been pointed out, is particularly adapted for operating upon work which has internal ey lindricai surfaces disposed at approximately. a

45 angle to the horizontal, such as are found in the motor blocks of V-type'automotive engines. Thespindles are preferably of a relatively flexible construction and consequently tools carried upon the outer ends thereof will, through the force of gravity, normally tend toflnd a position.

vertically relative to the point of suspension. It is therefore an aim of the present invention to provide means for maintaining the spindlesvin diagonal position and for guiding the tools carried thereby into 'the work. Moreover, it is necessary to supply a coolant fluid to the work while a tool is operating thereon, and with the cylinders diagonally disposed it is necessary, after a block has beenmovedinto position, to make adequate provision for conducting the coolant to the interior of the cylinder bores. The present invention, therefore, contemplates means not only for guiding a tool to the cylinder bore but also means operative after the movement of the block into position to conduct the coolant to the cylinder bore positively, without splash and man efflcient manner to produce the desired results.

One form of mechanism that has been found desirable for the purposes outlined comprises a pair of arch-like frame members I8 which are secured in any suitable manner adjacent the opposite ends of the work support I8 on flanges ll formed at the upper edges of the work support. The spacing between the frame members i 18' is preferably substantially equal to the length Each frame member 18 has formed on its inwardly facing side a pair of, bracket members It '(Figs. 2 and 4). These members are internally bored and adapted to receive stationary rods I5 which are secured therein by means of pins I8. The rods I5 are of substantial-diameter and are slidably engaged by guide casingsll on their outer .ends. :To form a substantially frictionless sliding contact with the rods, the casings ll have highly finished bearing bushings 78 therein.

Each of the casings I'I has formed on its inner side a pair of spaced parallel flanges 88 and M adapted to engage securely the end ofa jig member 82. An extension 83 having a lateral slot 88 is formed at each end of the jig members 82 to receive a knuckle arm 89 of a bell crank lever 88 which is rigidly mounted on the end of a stub shaft 88 suitably journalled in the frame member 18.

An upstanding arm 89 of each bell crank is pivotally connected at its upper end with the op- .posite crank on the same frame member I8.

Thus, a bifurcated lug 98 is provided on one end of each of a pair of cylinders 92 and is pivotally connected to one of the crank arms 89. A yoke 93 is pivotally connected to the opposite crank arm 89 and is secured to one end of a piston rod 94 by means of an adjustable screw connection 95. The other. end of the rod 94 extends into the cylinder 92 and has a piston 98 thereon.

,When the arms 89 are pivoted away from one another, the bell cranks-will pivot on shafts 88 to carry knuckle arms 85 downwardly and thereby force the jigs 82 and the guide casings I1 to move downwardly on the rods I5. Conversely, when the arms '89 are retracted and moved toward each other the jigs and casings l1 will be moved upwardly on the'i'ods 15. At their inner edges each of the frames 10 is provided with a transverse flange 98, and upstandinglugs I80 are formed on said flange. These lugs are tapped I to receive stop screws IIlI which are'adjustable and extend therethrough and are adapted to limit the approaching movement of arms 89. Suitable lock nuts I82 are secured to the inner ends of stops I ill to fasten the samein adjusted position.

Each of the jig members 82 is of substantially rectangular cross section and is adapted to abut squarely against a diagonal face I08 of the block 28 (Fig. 4). Bores II" are formed in the jigs coaxial with the cylinder bores 21 in the block 28, and each of' the bores I81 has a bushing III! therein extendingsubstantially above the outer surface of the jigmember 82. The bushings H8 A conduit H5 is suitably connected to an inlet pipe H6 which is threadedly securedin the wall of the jig" member and connects with a longitudinal passage H8 communicating with ports H9 in the bushings H8. Coolant fluid is delivered through the conduit I I5 from any suitable source (not shown) and passes to the interior of bushings I I8 through the ports I I9 and is thus delivered to the cylinders 21 and tools H2 in the block 28. Any suitable means may be provided for controlling the flow of coolant incident to the operationof the jigs 82 or of the honing spindles 25 are preferably annular in form and.

are provided with a plurality of radially extending grinding stones I2I (Figs. 5 and 6) for engaging the cylinder walls to hone the same to a uniform mirror finish. Due to the force of gravi- 5 ty it is necessary to provide protective means for preventing abrasive damage to the bushings 'i I0 and the cylinder walls during the period of insertion and retraction of the hones. For this purpose hones having a plurality of radially ex- 10 tending rigidly secured fiber guide members I23 intermediate the hone stones I2I have been found desirable.

As an example of the operative arrangement of this form of hone, the stones 'I2I may be mounted on retractable backing members I24 which are provided with inwardly facing cam surfaces I25 and I26 engaging with a plunger I28 having complementary cam surfaces I30 and I3I. The ends of the backing members are enm gaged by encircling retaining springs I32 which tend at all times to force the cam surfaces I25 and I26 into engagement with the plunger I28. In many instances it is desirable to permit equalizing of the stones and in such case the .cam

:5 surfaces I25 and I3I may be omitted to permit relative lateral rocking movement of the stones. In order to operate the plunger I28 to force the stones I2I into engagement with the bores 21, outstanding pivotal levers I34, which are adapted 30 to engage with the inner wall of the bushing members IIO, are mounted on a member I35 forming part of the spindle 25 intermediate the hone H2 and the head 23. A stem I38 on the plunger is operatively connected with the levers 35 I34 so that when the levers are forced inwardly by engagement with the bushing I I0 the stem I38 will be moved to urge the plunger downwardly as viewed in Fig. 6. Thus the cam surfaces I30 and I 3| will bear against the cam surfaces I25 and I26 on the backing members I24 and force the stones I2I radially outwardly beyond the peripheryof the wipers I23 and into contact with the face of the cylinder 21. When the levers I34 are removed from the bushing I I0,

5 the springs I32 will cause the backing members I 24 to force the plunger I28 upwardly and thereby retract the stones I2I.

The upper ends of the casings 11 are provided with caps I31 tapped to receive square headed 0 bolts I38 which provide safety stops for limiting the downward movement of the reciprocatory heads 23 whereby insertion of the bones II2 within the cylinders 21 beyond a given point is prevented should a failure occur in the control mechanism to be hereinafter described. The upper ends of the rods 15 are provided with apertures J39 to permit a free range of adjustment of the stops I38.

The sequence of operations in a normal cycle 50 of operation of the'present machine comprises indexing or positioning the work piece, clamping the jig members in place on the face of the work, moving the reciprocatory head to bring the honing tools into operative relationship withu in the cylinder bores, operating'the tools through a given number of strokes, returning the head to starting position to remove the tools, unclamping the work, and finally replacing the work. These operations are preferably carried 70 on in sequence, and controls are provided to correlate the operations.

The indexing and clamping mechanisms are hydraulically operated, and a manually operable control lever I48 having a handle portion HI and 7 which is rigidly secured to the end of a shaft I43 by means of a key I45 provides a convenient single control for operating both of these mechanisms. The lever I40 is preferably mounted at one side of the knee 30, and the end of the shaft I43 is journalled in'a' closure plate I41 secured by means of screws I48 to the wall of the knee. A retaining collar I50 (Fig. 8) is secured to the shaft I43 at the inside of the plate I41, and the opposite end of the shaft is provided with a reduced end I5I -(Fig. 2) which is journalled in w a bearing I53 having a rim portion I54 secured by screws I 55 to the wall of the knee 30.

A collar I51 is rigidly secured to the outer end of the shaft I43 by means of a key I58 (Fig. 9)

and is provided with a substantial integral radial 15 lug I60. A plate I62 is freely rotatable betweenthe collar I51 and the outer end of the bushing I53 and has outstanding eye lugs I64 and I65 on its outer face. The lugs I64 and I65 are internally threaded to receive similar stop bolts I88 20 and I61 which are held in adjusted position in the eyes by means of lock nuts I88. ,The ends of the stops I66 and I61 are positioned to be engaged by the lug I60 when the collar I51 is rotated oneway or the other by the shaft I43. 25 The plate I82 has oppositely extending arms I10 and HI which are respectively adapted to engage the ends of valve stems I13 and I14. The stem I13 is secured to a plunger I18 of a valve I18 for controlling the hydraulic operation of the 30 indexing mechanism, and the stem I14 is similarly connected to a plunger I19 of a valve I for controlling the hydraulic operation of the clamping mechanism.

A retaining collar I82 is attached adjacent the 35 outer end of each of the stems I13 and I14 and a compression spring I83 is placed between each of the collars I82 and aprojecting bearing portion I84 on the end of each of the valves I18 and I80. The compression springs I83 normally force each of the collars I82 and thereby the stems I13 and I14 to the left as viewed in Figs. 9 and 10, to carry the plungers I18 and I19 into one operative position, the other operative position of the plungers being attained when the springs are compressed.

A source of pressure fluid such as a sump I85 (Fig. 10) is conveniently provided in any desired part of the machine and a motor I86 drives a high pressure pump I88 and a low pressure pump I89 which withdraw fluid from the sump through intakes I90 and I9I, respectively. As pressure fluid is withdrawn from the sump I85 by the pump I89, it is forced through a branch line I82 into a main distributing line I93. A relief valve I is connected in the line I92 so that the pressure in the pressure fluid circuit supplied by the pump I89 will not rise above a predetermined point. The line I93 connects at'one end with a cross line I96 which is connected at opposite ends 60 to the valves I18 and, I80 to deliver pressure fluid through ports I98 and I99, respectively.

When the plunger I16 is moved to the left or right as viewed in Fig. 10, it will alternately cause the pressure fluid delivered through the port 5 I98 to escape through either a port 20I or a port 202, providing openings from the valve I18 to lines 204 or 205, respectively. The line 204 connects with a port 201 at one end of the indexing cylin- 'der 5| to receive pressure fluid to force the piston 70 58 to what will be termed the return" position ,of the indexing mechanism, and the line 205 will deliver pressure fluid to the opposite end of the indexing cylinder through a' port 209 to force the piston 50 in the opposite direction or 75 into the indexing" position.

The end of the valve I18 adjacent port 202 is provided with an exhaust port ZII and pressure fluid will escape therethrough into a return line 2I2 connected with .an exhaust 2I3 when the piston is being forcedto the return position. Adjacent the stem end of the plunger I16 there is formed a port 2 connecting with a longitudinal passage 2I5 through which exhaust fluid from the cylinder 5I is adapted to be returned to the return line2l2 during the indexing stroke of the piston 50.

The pressure fluid delivered to the valve I80 through the port I99 will be directed either through a. port 2" into a line 2I9, or through a port 220 and into a line 221, depending on the positions of plunger I19 in the valve. The line 2I9 connects with a branch line 223 which is connected to deliver pressure fluid through suitable ports at one end of the clamping cylinders 92, and the lineZZI is connected to a branch line 225 adapted to deliver pressure fluid through suitable ports at the opposite ends of the cylinders 92. When pressure fluid is delivered through the line 219 and the branch line 223, the pistons 96 will becarried to the opposite ends of the cylin-. ders whereby to extend the stems 9% toward their outer limits. Thus the arms 89 of the bell crank levers 86 are moved apart to cause downward movement of the knuckle arms 85 to carry the bosses 83 and the jigs 82 downwardly to cause the jigs to clamp against the faces of the block 28.

As has already been observed, the, springs 183 normally tend to urge the stems I13 and I11 and thereby the plungers I16 and I19 into one position. Thus, when the plunger I16 is in the lefthand position as seen in Fig. 10, pressure fluid will be transmitted through line 2011 and through the port 201 into the cylinder 5| to force the piston 50 to the return position of the indexing mechanism. When the plunger I19 is similarly in the left hand position, pressure fluid will be transmitted through the line 221 and the branch line 225 to deliver the fluid to the left end of the cylinders 92 and force the pistons 96 to the right to draw the arms 89 toward one another and thereby cause the jig members 82 to be retracted from clamping position to permit removal of the work piece.

the latter into engagement with the end of the plunger I14 during the full at-rest or, in the present instance, the horizontal position of the control lever I40. Thus the plunger I19 will be forced to the right as seen in Fig. 10 during the honing period and a constant supply of pressure fluid through the line 2I9 will cause the pistons 96 to maintain the clamping mechanism under compresslon.

The control lever M0 will be moved through a substantial arc in operating the controls, and when it is moved through the segment of the are indicated by 221 (Fig. 10) the lug will be correspondingly moved to release pressure against the stop I66, thereby permitting the compression spring I83 to forcestem 11d and plunger I19 to a the left so that pressure fluid will be directed through the lines 221 and 225 to force the pistons 96 into unclamping position. During the unclamping operation pressure fluid from the right ends of the cylinders 92 will escape through lines 223 and 2I9 through an exhaust port and outlet 229 to the return line 2 I2.-A-port 230 in the plunger I19 opens into a passage 23I and provides for exhaustion of pressure fluid to the return line 2 I2 duringthe clamping operation.

In order to secure a relatively smooth transition from the clamping to the indexing operation, a substantial lost motion is provided between the lug I60 and the stops I66 and I61 so that the clamping mechanism will be entirely open before the indexing mechanism is operated to position another Work piece thereunder. Thus, while the operating lever I40 is moved through a segment the plunger I13 upon engagement of the stop I61 by the lug I60, whereby to force the plunger I16 to the right as viewed in Fig. 10. Pressure fluid will then be delivered to the indexing cylinder to' actuate the piston 50 and the piston rod 52 to carrythe indexing carriage 15 through its indexing movement. It is desirable to provide means for preventin retraction of the operating lever Mil until the indexing operation is complete. That is, the operating lever should not be removed from that position in which the lug I6!) is effective to force the arm I10 of the plate 162 into engagement with the stem I13 until indexing of a work piece is completed. A form of means suitable for locking the operating lever may comprise an hydraulically operated interlock 2315 (Figs. 8 and 10). The interlock comprises a plunger 238 suitably secured at its inner end to a piston 239. A cylinder MI] is attached to or may form a part of the cover plate 11 and is provided with an internal cylindrical bearing surface 242 with WhlCh'thB piston 239 is in engagement. The plunger 23B is adapted to be slidably projected. through a suitable aperture in an auxiliary closure plate 2%, and a compression spring 246 normally forces the plunger into projected position. A stop collar 2&1 is secured adjacent the inner end of the plunger 238 by means of a pin 2 18 to limit outward movement of the plunger under the influence of the compression spring M6 and to provide a spaced relationship between the piston 239 and the inner face of a packing gland 250 which provides a fluid tight seal about the plunger 238.

A pressure fluid line 252 is connected with a port 253 at the end of the indexing cylinder 51 adjacent the port 201. During the period when the piston 51) is being forced to return position, the line 252 is. adapted to convey pressure fluid to the cylinder 2M through an inlet port 255 which connects with a passage 256 in the wall of'the cylinder. A port 251 opens to the space between the piston 239 and the gland 2% adjacent the collar M1, and the pressure fluid will force the piston to the left as viewed in Fig. 8, to compress the spring 266 and to draw the outer face of the plunger 238 flush with the surface of the plate 2%. Thus, the plunger 238 will only extend beyond the face of plate 2% during the indexing operation when pressure fluid is being exhausted from the indexing end of the indexing cylinder, and will be retracted during all the remainder of the time. An angular passage 2'59 in the wall of the cylinder 243 connects with the space-at the rear of the piston 233 and is adapted to receive any pressure fluid that may escape between the piston and the bearing surface 242 and convey the fluid to a port 233- for removal through a pressure fluid on the indexing side of the piston will be delivered through the line 232 to the interlock 236 and thereby cause the plunger 238 to be retracted and allow the operating lever I43 to be returned toward starting position.

While the interlock 236 provides an effective control to prevent retraction of the operating lever I43 until the indexing stroke of the indexing mechanism is completed, it is desirable to provide additional means to further control movement of the operating lever inorder to insure against operating the clamping mechanism until a work piece is properly positioned to receive the jigs 32 in a manner such that there will be an accurate coaxial alignment of the cylinders 21 and the bushings I I3. To this end suitable means are provided for automatically controlling the movement of' the shaft I43 after the interlock 236 has been actuated to retract the plunger 233 to release the operating lever I43. This means may comprise one or more centering pins 266 (Figs. 2 and 3) having substantially rounded tapering upper ends and being secured to a reciprocable element herein shown as a bar 261 which is slidably mounted in a bearing 233 attached to the bridge member 32. The block 23 is provided with one or,.more centering apertures 21I into which the pins 263 are adapted to enter after the work piece. has been placed in position under the clamping mechanism by means of the indexing mechanism.

A helical driving gear 213 is keyed to the shaft I43 and meshes with a driven helical gear 215 attached to the end of a shaft 213 which is journalled in one or more support bearings 213 suspended from the bridge 32. A spur gear 213 is keyed to the shaft 213 and meshes with a rack 233 milled on a face of the bar 261. Thus, when the operating lever I43 is raised toward a vertical position, the gear 213 will be driven clockwise as viewed in Fig. 2, to rotate the shaft 216 and the spur gear 213, whereby the bar 261 will be moved downwardly to withdraw the centering pin 233 from the work piece. The gear relationship is predetermined to effect insertion and removal of the centering pin 233 during the movement of the operating lever through the segment 233 of the arc of movement, which corresponds to the lost motion movement of the lug I33. Hence the centering pin 233 will be completely removed from the aperture 2" before the indexing mechanism is rendered operative to position another work piece in place. 'On-thc other hand, the centering pin 233 must be com-.

pletely inserted within the aperture 2" of a work piece before the operating lever I43 can be moved through the segment 221 of its arc of movement to carry the lug I33 into engagement with the stop I33 whereby to move the arm "I of the plate I62 into engagement with the end of the stem I14 of the valve I33 to; shift the plunger I13 to the position shown in Fig. 10 so that pressure fluid will be delivered to the cylinders 32 to operate the clamping mechanism.

The indexing and clamping operations are closely followed by the honing operation and it is therefore preferred to correlate the operation of the reciprocatory heads 23' supporting the spindles 25 and hones II2 with the operation of the indexing and clamping means'. The heads 23 are preferably hydraulically operated and it is desirable to control operation of the same electrically by means of conveniently centrally located switches so arranged that either head 23 may be operated independently or both heads may be operated simultaneously. Each of the heads 23 is preferably similarly operated and a description of the electrical and hydraulic circuits used in the operation of one will therefore sufllce for both.

In order to reciprocate the head 23, a piston rod 213 is attached to the upper-end thereof and extends into a stroking cylinder 213 suitably mounted on the main housing I3. A piston 211 is attached to the inner end of the piston rod 213 and is adapted to be reciprocably moved within the cylinder 213 by the force of pressure fluid alternately delivered to opposite ends of the cylinder through pressure lines 213 and 233 communicating through ports 232 and 233, respectively. The opposite ends of lines 213 and 233 lead to ports 236, and 233, respectively, in a main control valve 233. A plunger 233 having piston enlargements 233 and 23l at opposite ends and a spaced relatively narrow intermediate piston disk 233', which divides the space between the piston enlargements into a pair of chambers, is reciprocable in the valve 238. The piston disk 233 is alternately moved to opposite sides of an intermediate port 233 through which the pressure fluid is delivered to the valve 233 by a high pressure fluid line 236. Pressure fluid will thus be directed alternately through ports 235 and 233 into the fluid lines 213 and 233 leading to opposite ends of the cylinder 213.

A check valve 231 is interposed in the line 233 so that when the piston 211 is at the top of its stroke as shown in Fig. 10, the pressure fluid supporting the same will not return through the line until a predetermined pressure is built up by the flow of pressure fluid to the upper side of the piston through the line 213. Thereupon the pressure fluid will exhaust through the valve 233 and into an exhaust outlet 233 leading to an exhaust line 233 connected to an exhaust return line 333, which will return the fluid through the exhaust 2I3 to the sump I33. An exhaust outlet 33I is alsoconnected to the exhaust line 233 for the return of pressure fluid from the cylinder 216 through the line 213 at the up stroke of the piston 211.

The head 23 must be rapidly reciprocated and for this reason it is necessary to supply fluid under relatively high pressure to the stroking cylinder 216. The high pressure pump I33 forces the pressure fluid through a line 333 which communicates through a port 334 with an auxiliary control valve 336. This valve has a reciprocabie plunger 331 provided with a pair of spaced piston enlargements 333 and 3I 3. A stem 3I2 is attached to one end of the plunger 331 and extends through the wall of the column I6 for pivotal attachment by means of a yoke 3 to an arm of a bell crank lever 3I3 which is pivotally support 321 through which the line 296 communicates With the'valve 305. A port 323 which leads to an outlet line 324 connected to the return line 308 will then be open and the high pressure fluid will. return directly to the sump l85. A relief valve 326'is connected into the line 383 to prevent the building up of excessive pressure within the hydraulic. circuit supplied by the pump 188.

The valve 385 is preferably electrically controlled, and to this end an armature arm 328 of a solenoid 328 is pivotally connected to an arm 338 of the bell crank lever 315. -An electro-magnetic coil 332 surrounding the armature arm 328 is adapted to be energized by electrical energy received from any suitable source through leads 333 'and 334. A normally open electro-magnetic switch 336 is connected in series in the lead 338 and is adapted to be vclosed by ,the closing of a normally open starting switch 331 which is connected in series in an electrical circuit comprising leads 382, 383, 338, 339, 348 and 331. The circuit is connectedto a suitable source of electrical energy through the leads 341 and 332 and when the circuit is closed by the switch 331 a coil 386 of the switch 336 will be energized to close the latter switch. The solenoid coil 332 is then energized, and the armature arm 328 will be drawn inwardly to rotate the bell crank 315 and thus in series with a normally open master switch 388 having an actuating arm 388 (Figs. 7 and 10.) which is mounted on the outer wall of the knee 38 adjacent to the operating lever 188. The actuating arm 389 is adapted to be engaged by a lug 351 on the lever I88 when theleveris in the atrest position to thereby close the switch 3 18. A

normally open starting switch 352 is connected in series in a lead 353 of an electrical control circuit for the opposite side of the machine, and this lead is connected to the lead 338 in parallel with the lead 333. It will thus be evident that until the operating lever 188 is in the position in which the clamping mechanism is operated to secure the jigs 82 against a work piece, the switch 388 will remain open and the control circuits for neither side of the machine can be closed by the switches 331 and 352. The control lever M0, therefore, serves as a master control over all operations of the machine. 8

The means for controlling the reciprocations of the head 23 may be of a similar character as that disclosed in Patent No. 1,945,045 issued to A. M. Johnson on Jan. 30, 1934, and is diagrammatically illustrated in Fig. 10 only in so far as it is neces-' sary to an understanding of" the operation of the present machine. Thus, there is provided a stop bar 353 which is rotatably associated with the head 23 and connected for reciprocation therewith by a bracket 351. Stops 356 and 351 are adjustably secured in spaced relationship on the bar 353 and a skip stop 359 is secured intermediate stops 356 and 351. A plate 361 is slidably mounted in suitable guide means 361 (Fig.

1) supported by the housing 20 adjacent to the bar 353 and has alaterally extending operating arm 362 thereon adapted to been'gaged by the stops. An eccentric cam slot 364 is formed in the plate 361 and is engaged by a roller 365 carried by the end of a link 361 which is pivotally connected to a crank arm 368.

The other end of the crank arm 368 is rigidly" register with a branch 316 on the low pressure line 183. A line 318 leads to a port 319 in one end of the valve 288 and a line 38! leads to a port 382 in the opposite end of the valve. Upon rotation of the rotor 312 the passages 313 and 318'wil1 alternately form a direct passage between the branch 316 and the lines 318 and 381 so that pressure fluid from the line 193 will enter f rst one end and'then the" other end of valve 288 to reciprocate the plunger 283 and move the piston disk 233 first to one .and then to the other side of the port 293.

The rotor 312 of the pilot valve is caused to rotate synchronously with the reciprocations oi. head 23 and thereby controls the stroke of the head. Thus, when pressure fluid is delivered to the upper end of cylinder 216 whereby a'downward stroke is imparted to the piston. 211 and the head 23, the bar 353 will likewise be moved downwardly until the stop 351 engages operating arm 382 on the plate 361 and carries the same downwardly. Upon downward movement of the plate 361, the roller 365 will be moved in the cam slot 368 to carry the lever 361 to the right as seen in Fig. 10, and the crank arm 388 will be pivoted and cause the rotor 312 to rotate. While one of the passages 313 or 313 in the rotor forms a direct connection between the branch 318 and one of the lines 318.or 381, the other passage forms a connection between either of lines 318 or 38! and exhaust return line 298 so that as pressure fluid is delivered to one end of the valve 288 the fluid in the opposite end will be simultaneously exhausted.

When the head 23 is forced downwardly by piston 211 until the stop 351 engages the operating arm 362 and therethrough causes the rotor 312 to reverse the pressure fluid to the valve 288, the hones i 12 will be positioned at the lowermost reach to which it isdesired to insert the same within the cylinders to be honed. At this point,

of course,- the stroke of the head 23 will be reversed to withdraw the hones. However, the honing operation normally contemplates a substantial number of reciprocations oi. the hones within the cylinders, and a pawl 388 is therefore arranged on the skip stop 359 to engage the arm 382 'before the head 23 has returned sufliciently to remove the hones from the cylinder bores.

The pawl is yieldably extended into the path of the operating arm 362 so that the skip stop 333 may move freely past the arm on the initial down stroke. Upon upward movement of the bar 353, however, the pawl will engage the arm 362 to move the plate 361 as heretofore described. Thus, reciprocation of the head 23 will be limited to a distance equal to that between the stops 38! and 359, which distance is predetermined for the stroke desired for the hones within the cylinder bores being operated upon.

After the honing tools have beeninserted in operative position within the cylinder bores, the tools must be rotated as well as reciprocated in order to produce the desired grinding effect on the cylindrical surfaces. To this end suitable means are providedin the housing I9 and the columns 28 for imparting rotary motion through the spindles 25 and thereby to the hones H2. A desirable formof such means is disclosed in the aforementioned Patent No. 1,783,019, and may be employed in all its essential detail in the present machine. Thus, there is provided a drive motor 388 connected with a suitable source of electrical energy through power lines 38! and adapted to drive the gear mechanism (not shown) for rotating the spindles 25.. The present invention, however, contemplates certain improvements in the control of the said means.

Operation of the drive motor 388 is controlled by a magnetic powerline switch 389 which is connected to the lead 342 and leads 39! and 393, the latter lead being connected with the lead 34!. A normally closed switch 394 is interposed in the lead 342, and a normally open switch 385 is connected in series in the lead 39!.' In order to close the magnetic switch 389 and start the motor 388, the switch 398 is closed to close a preliminary electric circuit through the leads 34!, 383, 39! and 342 which energizes an electro-magnet 398 of the switch 389 to close the switch contacts and complete a continuing circuit through the leads 34!, 383 and 342. The latter circuit will then remain closed and keep the power line switch closed until the switch 394 is opened to interrupt the circuit, which will then allow the electro-magnet 398 to become inoperative and open the power line switch to stop the motor 388. Power from the drive motor 386 is transmitted through a shaft 398 to a shaft 399 by means of a suitable clutch 488. Rotary motion should only be imparted to the honing tools during the honing operation, and the same are preferably maintained nonrotatable at all other times. Im-

proved hydraulic control means are therefore contemplated by the present invention for synchroniz'ng the rotation of the bones with the other operations of the machine. In a preferred form of this control means, a bell crank 482 has a shifter arm 483 engaging a conventional annular, channeled shifter collar 484 connected to a, clutch element 488 adapted to engage the clutch upon clockwise movement of the bell crank 482 as viewed in Fig. 10. The opposite arm of the crank 482 is pivotally connected to a piston rod 48! which is attached at its opposite end to a piston 488 reciprocable in a cylinder 489. The cylinder 489 is provided at its opposite ends with ports .4i8 and 4!! which provide inlets for pressure lines 4 i2 and H3, respectively. lZ'he lines 2 and 3 connect with a control valve 5 through ports 8 and 4!! therein, and pressure fluid is delivered to the valve from the pressure line I93 through a port 9.

A bar 42! is slidably mounted parallel with the auxiliary housing 28 and .is adapted at its lower end to freely contact the head 23. Downward movement of the bar 42! is limited by a stop 42,! calculated to permit the bar to follow 'the descent of the head to a position short of the upper limis of its honing stroke. Near its upper end the bar 42! is provided with a weight in the form of a cam member 422 for gravita tionally moving the bar downwardly and for engaging with a roller 423 mounted at the end of a stem 424 which is connected at its opposite end to a. plunger 428 within the valve 4l5. A compression spring 428 is adapted to normally urge the stem 424 to the right as viewed in Fig. so as to maintain the roller 423 in the path of the cam 422. The position of the cam 422 on the bar 42! is such that when the head 23 moves in a down stroke the bar 42! will follow until halted by the stop 42!, and the roller 423 will ride out of engagement with the cam and allow the stem 424 and the plunger 428'to move to the right, whereupon the port 4!! will be placed in communication with the port 9 and pressure fluid will pass through the line 4!3 to the back of the piston 488. The piston rod is thus moved outwardly to rotate the bell crank 482 clockwise and cause engagement of clutch 488 to cause rotation of the shaft 399 and thereby actuate the mechanism for rotating the spindles 25. The cam 422 is preferably of a length such that the roller 423 will ride thereon until the head 23 has moved downwardly sufficiently to carry the honing tools within the bores to be honed. A port 438 in the end of the valve 5 allows fluid to exhaust to the return line 388 when the port 8 is uncovered by the plunger 428, and a passage 43! through the plunger 428 communicates through a port 432 through which fluid may exhaust from the line 4!3.

The hones !!2 need only be reciprocated and rotated for a predetermined length of time in order to effect the desired results, and it is therefore advantageous to provide means whereby operation of the honing machine may be easily and conveniently automatically controlled to withdraw the hones from the work and stop the machine at the end of a given period of operation. A desirable form of control for this purpose is disclosed in the aforementioned Patent No. 1,945,045 and includes a stroke counting mechanism operated by the reciprocations of the head 23.

Without entering upon an elaborate description of the details of the counting mechanism, it is suflicient for the present purpose to point out that the same comprises a counter 432 including a pinion 433 adapted to engage with a rack 438 on the bar 42!. The counter 432 is fixedly mounted upon a suitable bracket 438 rigidly secured to the auxiliary housing 28. A lever arm 438 is associated with the plate 38! and as said plate is reciprocated by engagement of the arm 382 with the stops on the bar 383, the arm 438 will actuate a shaft 439 associated with the mechanism within the counter432.

The counter may be adjusted so that after a predetermined number of reciprocations of the plate 38! a trip mechanism will close a switch 44!, thereby closing a. circuit through leads 442 and 443. The lead 442 is connected to the lead 342 and the lead 443 is connected to one end of an electro-magnet 448 of a switch 448. The other end of the electro-magnet 448 is connected by a lead 448 directly or through the lead 383 to the lead 34!, so that upon closing of the switch 44! a circuit will be completed through the leads 442, 443, and 448 to energize the electro-magnet 448 and close the switch 448. The switch 448 is connected in series in a power lead 488, one end of which is connected to a solenoid 48!. A lead 482 is connected to the opposite end of the electro-magnet of solenoid 48! and leads to a suitable source of electrical energy. When (5 moved through the final segment 216 of its arc of movement the plunger 233 will prevent return movement of the lever. When the indexing stroke of the iston 56 is completed and the work piece 28 has been fully positioned by the indexing mechanism, the port 253 will be opened to the pressure fluid and the plunger 233 will be retracted to allow the operating lever I 40 to be returned toward initial position.

As the operator returns the lever- I46, theplate I62 will be pivoted so that the arm I16 releases the stem I13 and allows the plunger I 16 to return to the left and open the port 2M to the pressure fluid which is delivered through the line 264 to the indexing end of the cylinder 5|. The piston 50 and the indexing carriage 4 5 are thus returned to starting position so that the pawl 4I will engage behind another succeeding workpiece to be operated upon in the next cycle of operation. The centering pins 266 will then be raised into engagement with the apertures 2' in the block, and the valve I86 will be actuated to open port 2 I 1 and allow pressure fluid to enter through the line 2 I 9 'to the cylinders 92 to actuate the pistons 96 and clamp the :Ilgs 32 in place. When the operating lever is-returned to its at-rest position, thearm 343 will be engaged to close the master control switch 343 between the leads 343 and 3330f the electric control circuit.

Thereupon everything is in readiness for the honing operation and the operator will close one or both of the normally open starting switches 33.1 and 352 to close the circuit for energizing the electro-magnet 346 which closes the switch 336 whereby the circuit for energizing solenoid 323 is completed. Thereupon, the plunger 361 01' the valve 305 will uncover the port 32I and allow highpressure fluid from the pump I66 to be delivered through the line 236 to the, valve 268. Thence the pressure fluid will travel through the line 219 to the-upper end of the stroking cylinder 216. Downward movement of the piston 211 will carry the piston rod 216 and the reciprocating head 23 downwardly to carry the honing tools H2 from the guide bushings Ill into the cylinder bores 21, The operating levers I34 will engage the innersurfaces of the bushings IIIl approximately coincident with the complete entry of the honing tools into the cylinder bores and operate to force the plunger I23 within the honing tools into engagement with the'cam races on the backing members I24 which will then carry the grinding stones I2I beyond the peripheral limits defined by the fiber guides I23 whereby the grinding stones will engage the walls of the cylinder bores 21.

Downward movement head 23 carries with it the ciated cam member 422 so the end of operating stem the said cam and the stem will be moved to the right under the influence of spring 428. Movement of the stem 424 carries with it the cam block 469 and the plunger 426. The switch 465 is closed by the cam block 463. Thus, the operbar 42l and the asso- 424 will ride oil of the initial downward the line 3 into the 'piston 408 to force the same to the left whereby of the reciprocating that the roller 423 onator must maintain stroke of the head is substantially under way and the switch 465 is closed, whereafter the energizing circuit for the switch 336 will remain closed until the cam 422 is returned to its upper position to engage the roller 423 and move the stem 424 back into starting position.

When the the port 4I'Iin the valve 4| 6 will be uncovered to permit pressure fluid to be delivered through cylinder 409 in back of the to operate the bell crank 462 and engage the clutch 406 to transmit power to the shaft 399 from the continuously running drive motor 336,

which is independently controlled, to rotate the spindles 25 and the honing tools H2.

The stops on the bar 353 serve to define the reciprocations of the head by engaging the arms 362 to move the plate 36I and operate the pilot valve 316 which controls the valve 233. After the head 23 has through a stroke amplitude defined by the distance between" the stop 351 and the pawl 334 of the stop 359, the counter 432 will operate to close the switch I. Thereupon the circuit for closing the electro-magnetic switch 446 will be closed and the energizing circuit connected with the solenoid 45! will be closed to operate the solenoid and-rotate the bar 353 to remove the stop 666 from operative engagement with the operating arm 362 and allow'the reciprocating head 23 to return to starting position. Then the switch 465 will be opened, the hydraulically operated clutch 400 will be disengaged, the solenoid 329 will be deenergized, and operation or the head 23 and the associated hones will'be stopped.

From the foregoing it will be apparent that the present invention provides an ingenious arrangement of hydraulically and electrically controlled mechanisms constituting an improved honing machine which is closely correlated in operation, is easily COIltl'OllEdyDlOVidGS for quick adjustment of the work and is durable and etflcient in use.

I claim as my invention:

1. A machine for truing the bores of the cylinders of a V-type the like comprising, in combination, a pair of oppositely disposed reciprocatory members supporting rotatably mounted spindles vcarrying honing tools operable upon converging axes, a support between said members and adapted to receive .a work piece to be operated upon by said tools, guide members for receiving said tools to the switch 331 closed until plunger 426 is moved to the right intcrnal'combustion engine or reciprocated anumberof times maintain the same in accurately defined axial relationship to same into position, said guide members being movable into substantially sealing engagement said work and, for guiding the with said work, and means within said guide in operation upon said work.

2. In a machine for truing the bores of the members for delivering coolant to said tools when cylinders of a V-typeiinternal combustion engine cured to said'support and including movable elements adapted to be engaged with said work to clamp the same on said support in position to receive said honing tools, means for delivering the switch 446 is closed the circuit through the leads 45D and 452 will be closed to energize the solenoid 45l which has an armature arm 454 pivotally connected at its outer end to a crank arm 455 secured to the bar 353 adjacent its upper end. When the solenoid is energized the arm 454 will be drawn to the left as seen in Fig. 10, to turn the crank arm 455 and rotate the bar 353, whereby the stop 359 will also be rotated so that the pawl 384 will be moved out of the path of the operating arm 362. The head 23 will then move up through an abnormal stroke until the arm 362 engages the stop 35%, and the honing tools will be disassociated from the work.

The rack 435 is only of such length as to en gage the pinion 433 during the upward movement of the head 23 to withdraw the tools from the work, that is, while the bar 35 3 is in movement with the arm 362 in position between the stops 359 and 355. The bar MI is cut away below the rack, so that the pinion is operatively associated with the mechanism for resetting the counter only during the abnormal stroke of the head 23. When the switch 44! is opened, the circuit through the leads 442 and 443 is broken and the electromagnet 445 will be deenergized to open the switch 446 and break the circuit through the leads 455 and 452 whereby the solenoid 45! will be deenergized and allow the bar 551i to assume its initial position.

At times it may be desirable to decrease the period of operative contact of the tools with the work and stop the rcciprocatory movements of the head 23 before the counter 432 closes the switch 44L Auxiliary manual as well as electrical control means are in the present instance provided for the purpose. lever 45? is secured to the lower end of the bar 11353 so that the bar may be manually rotated to shift the pawl 384 of the stop 359 out of operative position relative to the operating arm 362 to permit a premature abnormal stroke of the head 23 to return it to its uppermost position. In addition, a normally open switch 459 is connected in series in a shunt lead 460 and may be closed at the will of the operator to cut out the switch I and directly complete the circuit through the leads 443 and 448 to energize the electromagnet 445 and close the switch 446 to operate the solenoid 45! and thereby cause rotation of the bar 353 It may also become desirable at times to increase the time of the honing operation, and for this purpose a normally closed switch 4521s connected in series in the lead 442 so that the circuit may be kept open even after the switch 44I will normally be closed by the counter 432. This may be done at the will of the operator, who may keep the switch open as long as desired and upon releasing the same will close the circuit to operate the switch 446 and thereby the solenoid' An auxiliary circuit maintaining switch for controlling the stroking operation of the machine is provided to be operated by actuation of the stern 124, the movements of which are directly responsive to the stroke of the reciprocatory head 23. Thus, a normally open switch 455 has a contact member 4% attached to one end of a pivotal lever 451 which carries a roller 468 at its opposite end and is adapted to engage a cam block 4.69 supported by the stem 424. The switch 465 is connected to leads 4'?!) and 4H, and will be closed while the stem 424 is in the right hand Thus, an operating- 428 when the head 28 starts downward and during the time it is in the lower reaches of its reciprocatory movements. The cam block 469 then engages the roller 468 to move the lever 46? clockwise to carry the switch contact 466 across the contact points of the switch. When the head 23 is allowed to move to its uppermost position so that the com 422 engages the roller 423 which forces the stem 424 to the left, the circuit through the leads 342, 4'", 410 and 340 will be opened and the electromagnet 346 will be deenergized to allow the switch 336 to open to interrupt the energizing circuit for thesolenoid 329. Thereupon, the valve 305 will cut off the supply of high pressure fluid to the stroking cylinder 216 and the reciprocating head will be stopped.

In addition to the starting switch 352 for initiating the reciprocations of the twin heads 23 of the opposite sides of the machine and which is identical in function to the switch 331, there is provided a. switch 4'55 in series in a lead 416 and similar in function to the switch 395. Likewise, a plurality of control switches t, 418 and 419, corresponding in function to the switches 594, 459 and 462, respectively, are connected in series with a lead 485, which is connected in parallel with the lead 542. In practice the switches of similar function are placed close together so that an operator may open or close any individual switch, or with one hand may simultaneously actuate the similarly functioning switches for both sides of the machine. Preferposition into which it will be urged by the spring ably the switches are of the push button type and are all arranged together in a limited area, such as on a suitable panel at a conveniently located part of the machine.

Briefly summarized, the operation of the machine is as follows:

Assuming that the position of the apparatus and controls as shown in Fig. 10, represents the completion of the honing operation upon one of the cylinder blocks 28, the operator will raise the operating lever Mil through the segment 22'! of its arc of movement, whereupon the arm I'll of the plate I82 will release the stem H4 so that the compression spring I85 surrounding the same will force the stem and the associated plunger M9 to the left and thereby open the port 220 to the pressure fluid delivered through the lines I93 and I98. The pressure fluid will be delivered through the line 2% to the pistons 92 to force the same to the right and thereby unciamp the jigs 82 from each oi the bevelled faces of the block 25.

Then the operator further moves the lever I48 through the arc segment 233 and the rotation of the shaft M3 will drive the spiral gear 213 and cause the gear 215' and the associated shaft 275 to rotate clockwise as viewed in Fig. 2 so that the pinion 219 which is in mesh with the rack 285 will carry the one or more shafts 261 downwardly to remove the centering pins 265 from the apertures 2H in the workpiece 25.

The operating arm 540 will then be moved through the arc segment 254, whereupon the arm I'm of the plate H52 will engage the stem H3 and force the same to the right to uncover the port 252 so that pressure fluid will be delivered to the line 255 through which it is delivered to the return end of the cylinder 5!. The piston 50 carries the operating stem 52 with it to actuate the indexing carriage 45 so that the engagement face 63 of the pawl lever 4| will bear against the succeeding block 28 to force the same along the tracks 5!! into position under the frame memtrolled means for rotating said tools, electrically coolant to said worlr, and means carried bysaid elements for guiding said honing tools to said I work.

3. In combination in a honing machine, a pair oi tool carrying reciprocatory heads in substantial spaced relationship, rotatable honing tools carried by each of said heads, a work support between said heads and adapted operatively to support a work piece relative to said tools, means for reciprocating said heads, hydraulically conoperated means for controlling'the operation of said first mentioned means, and independent electric switches for controlling said electrically operated means for each of said heads, said switches being located in adjacent relationship on one part of the machine whereby said switches may be jointly or separately operated to initiate the reciprocation or said heads simultaneously or independently.

4. In a machine for simultaneously honing the I angularly disposed cylinders of a v-type cylinder block a pair of oppositely inclined reciprocatory members mounted to move axially of said cylinders, spindle means operatively associated with said members and terminating in hones having stones for operating upon the walls of said cylinders, means for clamping a cylinder block in position to receive the bones, means for guiding the hones into the cylinders. means associated with said hones for maintaining the hone stones inoperative until said hones have been positioned within the cylinders, and means for actuating ,said members independently or simultaneously to reciprocatethe hones.

e 5. In a machine for honing a diagonal cylindrlcal surface, in combination, a diagonally mounted reciprccable tool carrying member, a honing tool carried. by said member and includ-- ing abrasive means engageable with a diagonal cylindrical surface during operation of the tool as well as non-abrasive contact means to prevent damage by said abrasive means while thetool is being moved to or from engagement with said surface, an element for maintaining said tool in a given axial relationship and adapted to be placed into contact with a work piece having a to be driven thereby,

cylindrical surface whereby to guide the tool into operative relation with said surface, said nonabrasivecontact means serving to protect said element from damage bysaidabrasive means, and means operable incident to the movement of the tool into operative relation for rendering said abrasive means operative upon said surface.

6. In a honing machine, in combination.- a stationary work support, a pair of twin reciprocatory heads one at each side of said support,

rotatable members carried by said heads and adapted to reciprocate on converging axes, honing tools carried by said members and arranged hydraulically controlled means for rotatably driving said members, hy-

draullcally actuated means for reciprocating said heads, means actuated as an incident to the reciprocatory movements or said heads for governing the reciprocatory movements thereoi.',- solenoid operated valve means for controlling the .flow of pressure fluid to said hydraulically actuated means, and manually actuable electric control means for selectively eflecting the operation ot'said heads simultaneously or independently.

'7. A honing machine having, in combination,

a stationary work support, rotatable reciprocatory members mounted at opposite-sides of said support and adapted to reciprocate on converging axes, honing tools carried by said members and arranged to be driven thereby, hydraulically controlled means for rotatably driving said 'members, hydraulically actuated means for reciprocating said members, solenoid operated valve means for controlling the flow of pressure fluid 9. A honing machine having, in combination,

a stationary work support, rotatable reciprocatory members mounted at opposite sides of said support and adapted to reciprocate on converging axes, honing tools carried by said members and arranged to be driven thereby, means for rotatably drivingsaid members, means for reciprocat ing said members, and means for selectively eii'ectin'g the operation 01' said members simultaneously or independently.

10. In a honing machine 01 the class described, the combination of a reciprocatory head having rotatable spindle means operatively associated therewith, honing means carried by said spindle means, a support adjacent said head-for supporting work to be operated on by said honing means, means for indexing the work, means for clamping the work in place on said support, 'electrically' controlled means for reciprocating said head, lever controlled means for operating said indexing and clamping means, an electric control switch closable by contact with saidlever only when said lever is in position to operate said clamping means, and means i'or retaining said lever out of position to operate said clamping means until the workhas been indexed.

11. A machine for truing the bore 01' an internal combustion engine cylinder or having, in combination, a spindle carrying a hening tool, a support upon which the work is positioned with the axis oi the bore to be honed aligned with the axis 01" the spindle, means including a power sourcejor rotating the spindle, pressure fluid actuated means for effecting relative movement between the work and the spindle longitudinally of the latter, said pressure fluid actuated means having a main control valve and an auxiliary control valve. automatic means for operating said main control valve whereby to efiect continuous relative reciprocation with anormal stroke of a length determined by the length 01' the bore, means for controlling, saidautomatic means to produce'an abnormalstroke of a predetermined length such as to disassociate the tool and the work, independent means for operating said auxiliary control valve so as to stop relative longitudinal movement at the end of said abnormal stroke, and a hydraulically operated clutch operable incident to said abnormal stroke to disengage said means for rotating the spindle from said power source coincident with the stopping of the reciprocating means.-

12. In a machine of the class described, a reciprocatory tool carrying member, said member being reciprocable through a defined tool bpthe like,"

erative stroke as well as through an abnormal longer stroke, electrically controlled means for reciprocating said member, a normally open switch manually closable to initiate the operation of said electrically controlled means, an auxiliary switch closable as an incident to the reciprocations of said member and adapted to remain closed to maintain said electrically controlled means in operation during said operative stroke of said member, and means coacting with said tool carrying member to open said auxiliary switch as an incident to said abnormal stroke of said member to stop the operation of said electrically controlled means.

13. In a machine of the class described, a reciprocatory tool actuating member reciprocable through a defined tool operative stroke and through an abnormal longer stroke, means for reciprocating said member, a bar mounted to reciprocate with said member, automatic stroke counting mechanism actuated by the reciprocatory movements of said member, means controlled by said mechanism for movingsaidmember through said abnormal stroke after a predetermined number of' tool operative strokes, and means actuated by said bar for automatically halting operation of said'first mentioned means to stop the reciprocations of said member incident to said abnormal stroke.

14. In a machine of the character'described, a reciprocatory member operatively carrying a ro tatable tool, a work support arranged to receive a work piece to be operated upon by said tool, means for automatically positioning the work piece correctly on said support, a device movable toward said work piece for guiding said tool thereto and including means for delivering coolant to the work, coordinately controlled means for operating said device and said means for positioning the work, means for reciprocating said member, power driven means for rotating said tool, and means operable incident to the reciprocatory strokes of said member for controlling the operation of said power driven means.

15. In a machine of the character described, a reciprocatory member operatively carrying a rotatable tool for acting upon the cylindrical bore of a work piece, a support arranged to receive the work piece, means for automatically positioning said work piece on said support, a device movable toward said work piece for guiding said tool to said work and including means for delivering coolant to the work, common control means for synchronously operating said device and said means for positioning the work, means also operated by said control means for centering said work on said support, means for reciprocating said member and including operating means governed by said control means, power driven means for rotating said tool, and means operable inmember for controlling the operation of said clutch and said electrically actuated means.

. 17. In apparatus oi the character described, a

work support adapted to receive a work piece having a pair of diagonal faces in converging planes and bored'perpendicularly to said planes, 8. pair of members having openings therethrough and movable on axes defined to bring said members into engagement with the diagonal faces of said work piece with said openings in registration with the bores in said faces, and means operable to move said members simultaneously toward said faces.

18. In a machine of the character described adapted to operate upon a work piece having a face disposed diagonally to the horizontal, the

combination of a tool carrying member adapted to direct a tool perpendicularly to the diagonal face of the work piece, a tool carried by said member, stationary means for supporting the 'work piece in position for operation thereon by said tool, and a guide member positioned adjacent said tool carrying member and adapted to guide said tool to the work, said guide member being movably mounted relative to said supporting means and including means for delivering coolant fluid to the work and tool, and power actuated means for clamping the guide member into substantially sealing contact with the work to prevent escape of said fluid due to the diagonal position of said work face.

19. In a honing machine of the character described, in combination, a reciprocatory head having a rotatable spindle member terminating in a honing tool, a support adjacent said head and adapted to receive a piece of work to be perated on by said honing tool, a rigid frame on said support, a reciprocable member associated with said frame and adapted to be moved into engagement with said work to clamp the same in position on said support, and means for guiding said honing tool relative to said work including a bushing carried by said reciprocable member.

20. In a honing machine of the class described, the combination of a reciprocatory head, rotatable spindle means operatively supported by said head, honing means carried by said spindle means, a support adjacent said head for supporting work to be operated on by said honing means, indexing means for accurately positioning a piece of work relative to said spindle means, and means for clamping the work in place on said'support including means for guiding said honing means to the work.

21. In a honing machine of the class described, the combination of a hydraulically operated reciprocatory head carrying rotatable spindle means, honing means carried by said spindle means, a support adjacent said head for supporting work to be operated upon by said honing (means, hydraulic means for indexing a piece of work relative to said spindle means, and hydraulic means for clamping the work in place on said support.

22. In a machine of the character described, a support for a piece of work, means movable in a substantially. horizontal plane in engagement with the piece of work for moving said piece of vwork horizontally into position upon the support, means rigid with said support and carrying reciprocable clamping means for securing said work against movement on said support, and common means for operating said indexing means and said clamping means one after the other in the order named.

23. In apparatus of the character described, in combination, a support for a piece of work, indexing means for moving said work into position on said support, means for clamping the work in place after, said indexing means has n tioned the work, and common control means for successively actuating said indexing'means and said clamping means.

24. In a honing machine of the class described, the combination of a reciprocatory member having rotatable spindle means operatively associated therewith, honing means carried by said spindle means, a support adjacent said member for supporting work to be operated on by said honing means and including means for moving the work into position to be honed, a clamp for holding the work in place on said support duringoperation of the honing means, and manually operable means for controlling both said moving and clamping means. a

25. In amachine of the class described, the combination of a tool carrying member, tools carried by said member, a support for carrying a work piece in operative relationship to said tools,

means for automatically indexing a work piece .on

said support, means for clamping said work piece on the support in operative relationship to said tools, electrically controlled means for operating said member and tools, a manually operable control lever for controlling the operation of said indexing-and clamping meansfand an electric mas ter control switch operable by said lever as an'incident to the operation of said clamping means for controlling the operation of said electrically controlled means.

26. In a machine of the character described, a work support, hydraulically operated means for automatically positioning a work piece on said support, a control lever for, operating said hydraulically operated means, and an hydraulically operated interlock engageable by said control lever and operable incident to the operation of 'said hydraulically operated means to control the ated therewith, honing means carried bysaid spindle means, a support adjacent said memher for supporting work to be operated on by said honing means and including a device for indexing the work, clampingmeans adapted, to bear against the work during operation of the honing means, control means for the device and clamp, and an interlock'for preventing the operation oi said clamp until said device has operated toindex the work on said support. A

29. A machine of the character set forth, comprising, in combination, a tool carrier, a tool supported by the carrier, a support adjacent said tool carrier for supporting work to be operated upon by said tool, means for indexing the work by moving the same into tool operating position, means for engagement with said work to hold the same in indexedposition, means for clamp-- ing the work against said support, and a single control for successively operating each of said means.

30. In a machine of the character described, a tool carrier operatively supporting a tool, a support adjacent said carrier and adapted to receive a work piece to be operated, upon by said tool, means for positioning a work piece upon said support, an operating lever for controlling the operation of said means, and a centering pin actuated by movement of said operating lever to engage with said work piece after said means has operated thereon to position the same on said support.

31. A machine of the character set forth comprising, in combination, a tool carrier, a tool sup-- ported by the carrier, 'a support adjacent said tool carrier adapted to receive work to be operated upon by said tool, hydraulically operated means for positioning the work on said support, hydraulically operated means adapted to be clamped against said work when in position relative to said tool, separate valves for controlling the hydraulic operation of both 01' said hydraulically operated means, control mechanism for op- ;erating said valves including a' shaft having a valve actuating member and an operating lever thereon, a centering pin element for engagement with a work piece after the latter has been posi-' tioned on said support, andmeans actuable by the movement of said shaft by said lever for operating said element.

32. A honing machine comprising, in combination, means for supporting a V-type engine block in upright position with the cylinders inclined upwardly and outwardly and with upwardly and inwardly inclined upper end faces, a pair of tool supporting heads mounted above said block on- Opposite sides thereof for reciprocation parallel to the axis of the cylinders and having rotary honing tools for the respective cylinders, clamping means coacting with the inclined upper end races of the block to hold it in position during the honing operation, and means for reciprocating said heads simultaneously.

33. A honing machine comprising, in combination, means for supporting a V-type engine block in upright position with the cylinders inclined upwardly and outwardly and with upwardly and inwardly inclined upper end faces, a pair of tool- 'supporting heads mounted above said'block for reciprocation parallel to the axis of the cylinders and having rotary honingtools for the respective cylinders, means for reciprocating said heads in timed relation to eflect the simultaneous honing of all of said cylinders, and coolant supply means engageable with said inclined faces oi the block in liquid conducting relation to the cylinders thereof.

34. A-honing machine comprising, incombination, means for supporting a V-type engine block in upright position with the cylinders inclined upwardly and outwardly and with upwardly and inwardly inclined upper end faces, a pair of tool supporting heads mounted above said block on opposite sides thereof tor-reciprocation parallel to the axis of the cylinders honing tools for the respective cylinders, clamping means coacting with said upper end faces 01' and having rotary the block to hold it in position during the honing thereon, means for supporting an engine block in upright position between said heads with its cylinders coaxial with the respective spindles, means for guiding the honing tools into and out of their respective cylinders, and means for supplying coolant through the guide means to the cylinders, said supporting means for the block and said guide means being relatively movable to effect a substantially tight liquid seal between the block and the guide means.

36. In a machine of the character set forth, in combination, a tool carrier, a tool supported by the carrier, a support adjacent said toolcarrier for supporting work to be operated upon by said tool, and means for indexing a work piece on said support including a reciprocable carriage carrying a pawl adapted to engage said work piece to move the same into position upon actuation of the carriage, said pawl being mounted on an eccentric pivot with the heavier end extending rearwardly to maintain the forward end in a normal work engaging position, and a stop coacting with said pawl to maintain the rear end 01' the pawl positively below a plane wherein the same might catch upon a work piece.

37. In a honing machine or the like, a reciprocatory tool carrying member operable through a reciprocal cycle including in one part an opera-'- tive stroke and in another part a longer approach and return stroke overlappin said operative stroke, electrically controlled means for reciproeating said member, a normally open starting switch for initiating said reciprocal cycle, an auxiliary control switchfor governing operation of said electrically controlled means following initiation of said cycle, and a controller coacting with said member for operating said auxiliary switch as an incident to said reciprocal cycle and serving to maintain said auxiliary switch closed throughout said operative stroke and during part of said approach and return stroke beyond said operative stroke but eflective to open said auxiliary switch in the extreme return position of said member.

38. A honing machine for V-type engine blocks comprising, in combination, a substantially V- shaped supporting structure including an elonby the supporting structure closely adjacent opposite sides of the block and adapted to support and guide the honing tools during the insertion thereof into and withdrawal from the block, and power driven mechanism for driving said spindles and imparting a reciprocatory motion 'to said heads.

39. A honing machine for v-type engine blocks comprising, in combination, a substantially V- shaped supporting structure including an elongated horizontal base and upright supports at opposite sides of the base, tool heads mounted on the respective upright supports for reciprocation in paths disposed approximately 45 degrees from a median plane extending-longitudinally of the base, each of said heads having a plurality of rotatably driven tool spindles with honing tools flexibly suspended therefrom, means for supporting an engine block for movement longitudinally above the base into an upright position in operative relation to said honing tools, means carried by the supporting structure closely adjacent opposite sides of the block and adapted to support and guide the honing tools during the insertion thereof and withdrawal from the block, and power driven mechanism for driving said spindles and imparting a reciprocatory motion to said heads, said power driven mechanism including a separate driving means for the respective heads arranged for manual control from a common point and operative independently to impart reciprocatory motion to the heads and rotate the spiridies thereof.

40. An apparatus of the character described comprising, in combination, means for supporting work pieces for movement in a predetermined path, a pair of machine units disposed on opposite sides of said path and each having a reciprocable tool carrying member, means for reciprocating each of said members including a separate operation controlling mechanism for each of said members, means for rotating said members, means coacting with each of said members and responsive to the reciprocable movements of the latter for controlling the operation of said rotating means, and independent manually 0-perable elements for controlling each controlling mechanism, said manually operable elements being located adjacent one of said units and adapted for separate or joint operation to initiate reciprocation of said members independently or simultaneously.

d1. An apparatus of the character described,

comprising, in combination, supporting means for carrying work pieces for movement in a predetermined path, a pair of machine units disposed on opposite sides of saidpath and each having a vreciprocable tool carrying member, means for reciprocating said members including a separate electrically controlled operating mechanism for each of said members, and independent electric switches for controlling said operating mechanisms, said switches being located in adjacent relationship on one part of the apparatus for joint or separate operation to initiate reciprocation of said members independently or simultaneously.

42. An apparatus of the character described comprising, in combination, means for supporting work pieces for movement in a predetermined path, a pair of machine units disposed on opposite sides of said path and each having a reciprocable tool carrying member, separate hydraulically operated means for reciprocating each of said members and including separate electrically actuated control mechanisms; and separate electric switches for operating said control mechanisms, said switches having a common location on the apparatus for joint or separate operation to initiate reciprocation of said members simultaneously or independently.

43. In a honing machine for finishing internal cylindrical surfaces, at reciprocable tool carrier having a rotary honing tool thereon, a stationary work support, a jig member having a passage coaxial with the cylindrical surface to be honed, guide means for said member mounted on said work support and reciprocably supporting said member for movement toward and from the work support, said member being operative to clamp the work against said work support and to support and guide said tool in its movement into the work, means for moving the jig member into clamping engagement with the work, and means for moving said tool carrier to carry the tool through said passage into the work.

44. In a machine of the character described. areciprocable tool, supporting means for carrying a work piece in position within the operative range or said tool, power actuated means for moving the work piece into position on said supporting means, power actuated means for engaging said work piece to retain the same in fixed position on said supporting means, common control mecha-- nism for operating both of said power actuated means in the order set forth, and means operable by said control mechanism to initiate the recip= rocation of said tool said means being eflective until the work piece is in said fixed position to maintain said tool inoperative.

45. In a honing machine oi the class described,

to stop the reciprocations or. said tool carrying means after it has moved to one limit of said abnormal stroke, and means carried by said member and enacting with said last-mentioned means for operating the latter. 

